Let’s Take a minute to run down the basics of measuring , design and construction of Chilled or Hot Water Coils.
Materials of Construction and Sizing:
- Tube Size – Water Coils as a standard are either 1/2″ .020″ or .025″ copper tube wall thickness or 5/8″ tubing either .020″, .025″, .035″ or .049″ copper tube wall thickness.
- Fin Thickness – Standard Water Coils have options of .006″, .008″, and .010″ fin thicknesses.Casing Material – Most Water Coils as a Standard are 16 Ga. galvanized metal casing with options for stainless steel casing.
- Header sizes – The headers for a Water Coil can range from .5″ to 4″
- Fin Height – The Fin Height is the Length of the aluminum fin parallel with the header
- Fin Length – The Fin Length is the Length of the fin horizontal to the header
- Casing Height – Most Water Coils have casing on the top and bottom of the coil the casing height includes the fin height and both the top and bottom flanges of the casing.
- Casing Length – The casing length includes the tubes sheets on both the front and back of the coil and what are support the tubes running through the coil. Like the casing height the fin-pack and the both flanges on the casing are included in the casing length.
Tube Size/Fin Height/Fin Length – The tubes sizes are critical to confirming the fin height of a Chilled Water Coil or Hot Water Coil. 1/2″ tubes run on 1.25″ centers as an example – 20 – 1/2″ tubes running vertically would have a fin height of 25″. The same concept is true for 5/8″ copper tubes except they are running on 1.5″ centers as an example – 20 – 5/8″ tubes vertically would have a fin height of 30″.
Header Size – Duplicating the header and connection sizes is critical to ensuring that the proper GPM is allowed to flow through the coil at the correct fluid velocity and water pressure drop. Failing to properly do this can cause premature pitting of the copper tube and failure of the coil/pumps.
We look forward to assisting our customers in understanding the build and design of all HVAC Coils.